The USDA’s pending approval of soybean and corn varieties that are genetically-engineered to resist the herbicide 2,4-D doesn’t sit well with Oregon wine grape growers, who say it opens the door to more such crops, more 2,4-D use and more damage in their vineyards.

Approval of Dow AgroScience’s soy and corn varieties and of the company’s Enlist herbicide, a 2,4-D-glyphosate mix that can be used on them, is a more immediate concern to grape growers in the Midwest, where soy and corn are the major crops.

In Indiana, Purdue University’s Extension Service warned that phenoxy growth regulators such as 2,4-D can cause “significant injury” to grape vines even when applied at one-hundredth the rate advised on the label.

The Animal and Plant Health Inspection Service issued a final environmental impact statement this past week saying the new varieties, one corn and two soybean, pose no pest hazard to other crops and plants. APHIS, the USDA division that regulates genetically engineered plants, also has completed a draft environmental review of Monsanto soy and cotton varieties that resist another herbicide, dicamba. (http://www.aphis.usda.gov/publications/biotechnology/2014/faq_brs_eis.pdf)

Meanwhile, the federal Environmental Protection Agency is finishing its review of Dow’s Enlist herbicide. Opponents believe 2,4-D is a health hazard, pointing out that it was one of the ingredients used to make Agent Orange, a defoliant linked to health problems among Vietnam War veterans. The EPA banned another Agent Orange ingredient, 2,4-T, because it contains cancer-causing dioxins, but it considers 2,4-D safe.

Damage to grapes is the most pressing issue to Northwest farmers. Joel Meyers, founder of Vinetenders, LLC. in Oregon’s Yamhill County wine region, said USDA approval could lead to 2,4-D-resistant alfalfa, beets and other crops. He and other vineyard operators have sustained drift damage from 2,4-D use by grass seed growers and Christmas tree growers.

This past spring, the Oregon Winegrowers Association began distributing 18- by 12-inch warning signs that can be posted along roads or property lines. The signs read, “HELP PROTECT THIS VINEYARD. PLEASE DO NOT SPRAY HERBICIDES LIKE 2,4-D WITHIN 350 FEET.”

Seeking a permanent fix, growers have also asked the Oregon Department of Agriculture to ban 2,4-D use from April to October, the growing season when grape vines are most susceptible to damage. Washington state has adopted that restriction to protect vineyards in the Tri-Cities region.

The department appointed a committee to study the problem, but a 2,4-D ban is not likely, department spokesman Bruce Pokarney said. Instead, the department favors an education campaign aimed at farmers and at rural property owners who might spray blackberries, for example, without being aware of the potential consequences.

Meyers said he won’t harvest a seven-acre muscat grape vineyard this year due to drift damage. The department’s approach, he said, has already been tried.

“This education deal is not going to fly,” he said. “If it hasn’t worked in 15 years, it’s not going to work now.”

Meyers said increased 2,4-D use is the inevitable result of the USDA approval.

“All of the high value sensitive crops will have a higher risk of injury because more of it’s used and it’s used later in the season,” he said.

Opponents believe Dow AgroScience’s soy and corn varieties are a replay of Monsanto’s introduction in 1996 of “Roundup Ready” crops that could resist glyphosate, the key ingredient in the company’s herbicide. It resulted in heavy use of the chemical and excellent weed control at first, but at least 22 weed types have since developed resistance to glyphosate, according to a 2012 report by Purdue University. Dow’s 2,4-D product is intended to kill glyphosate-resistant weeds.

The Center for Food Safety, which opposes genetically modified crops, called the USDA’s pending approval an “outrageous abdication” of the department’s responsibility to protect Americans’ health and food supply.

“The Obama Administration has ignored the interests and demands of millions of Americans, Members of Congress, and scientists, farmers and health professionals,” Executive Director Andrew Kimbrell said in a prepared statement.

Fifty members of Congress, including Oregon Rep. Peter DeFazio, D-4th District, signed a letter to the USDA and EPA, saying the agencies have “failed to thoroughly analyze and address the risks” of the herbicide. The letter said 2,4-D-resistant crops will likely cause “multiple adverse human health, environmental, agronomic and socioeconomic harms.”